Gas jets or burners



Feb. 14, 1967 J. HANCOCK ETAL. 3,304,014

GAS JETS OR BURNERS Filed Sept. 4, 1964 2 Sheets-Sheet 1 F/GJ. H6. 6.

INVEMTOES ATTQQMEYS Feb. 14, 1967 J. HANCOCK ETAL 3,304,014

GAS JETS OR BURNERS Filed Sept. 4, 1964 2 Sheets-$heet 2 Iwvswroes United States Patent 3,304,014 GAS JETS 0R BURNERS John Hancock, Leeds, and Albert Westerman, Normanton, England, assignors to Geo. Bray & Co. Limited, Leeds, England, a British company Filed Sept. 4, 1964, Ser. No. 394,580 Claims priority, application Great Britain, Sept. 13, 1963, 36,188/63 7 Claims. (Cl. 239-548) This invention relates to non-aerated or difl usion gas jets or burners for use with slow burning gases in domestic or industrial gas appliances.

The design, manufacture and use of non-aerated jets composed of either ceramic material or metal and used for fast burning gases such as coal gas are well known in the gas industry but such jets cannot be used with slow burning gases such as methane or propane/air. This is because when slow burning gases are used with known jets, the flames tend to lift away from the orifices on which they are formed with resultant extinguishing of the flames.

According to the present invention there is provided a non-aerated gas burning jet having a cylindrical body portion provided with a main orifice which is rectangular in plan and is disposed at the upper end of the body portion at the apex of a substantially wedge shaped cavity formed within the body portion, said cavity being adapted and arranged to produce a fan shaped flame at the main orifice, and in which the body portion is formed with an annular shoulder in which are formed a plurality of auxiliary orifices providing, in operation of the jet, flames which serve to maintain ignition of the gas issuing from the main orifice.

The velocity at which gas leaves the auxiliary orifices is low, by design, and therefore the flames formed at the auxiliary orifices are stable at normal gas pressures. These flames provide a stable source of ignition at the base of the gas stream issuing from the main orifice and therefore the flame formed at the main orifice is constrained from lifting. By varying the form of the auxiliary orifices and their position relative to the main orifice, a wide range of fuel gases may be burned at the same level of heat output and at the same pressures as coal gas or other fast burning gases.

In a particular construction embodying the invention, the body portion is cylindrical and the main orifice is rectangular in plan and is disposed centrally of the upper end of the body portion at the apex of a wedge shaped cavity formed within the body portion. The cavity and the main orifice are such that a fan shaped flame is produced at the main orifice. The auxiliary orifices are provided in an annular shoulder formed externally of the body portion and are fed with gas from an annular groove formed on the underside of the shoulder. In turn, the annular groove is fed with gas from radial slots extending into the cavity in the body portion.

In another construction embodying the invention the auxiliary orifices are supplied with gas from a diametrally disposed groove formed on the underside of the shoulder and body portion of the jet, the groove being in communication with an annular groove formed in the upper surface of a socket in which the jet is mounted. The exits from the auxiliary orifices may be disposed below the exit from the main orifice or they may be coplanar therewith and the auxiliary orifices may be formed in frus-to conical projections from the upper face of the shoulder. Preferably, the jet is a press fit into a screw-threaded member which is received by a gas supply pipe. The screwthreaded member enables the jet to be orientated in any desired direction.

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Jets embodying the invention will now be described in greater detail by way of example, with reference to the accompanying drawings in which:

FIGURE 1 is a sectional elevation of one embodiment,

FIGURE 2 is an underside plan of FIGURE 1,

FIGURE 3 is a partly sectional elevation of the jet shown in FIGURE 1 assembled with a further component,

FIGURE 4 is a sectional elevation of another embodiment,

FIGURE 5 is a plan of FIGURE 4,

FIGURE 6 is a partly sectional elevation of the jet shown in FIGURE 4 assembled with further components,

FIGURE 7 is a sectional elevation of a further embodiment,

FIGURE 8 is a plan view of FIGURE 7,

FIGURE 9 is a sectional elevation taken at with respect to FIGURE 7,

FIGURE 10 is a sectional elevation of a still further embodiment,

FIGURE 11 is a plan view of FIGURE 10; and

FIGURE 12 is a sectional elevation taken at 90 with respect to FIGURE 10.

Referring to FIGURES 1 and 2, the jet has a cylindrical body 1 formed with an annular shoulder 2. The upper end of the body 1 has a centrally disposed rectangular main orifice 3 at the apex of a wedge shaped cavity 4 and formed in the body 1. The shoulder 2 has a series of auxiliary orifices 5 formed therein leading to an annular channel 6 in the underside of the shoulder 2. Two diametrically opposed radially extending slots 7 connect the channel 6 to the cavity 4 within the body 1. The jet is made a press fit into a recess 8 formed in a screwthreaded metal socket 9 having an axial gasway 10 (FIG- URE 3). The jet is made a gas-tight fit in the recess 8. The socket 9 is screwed into a gas supply pipe, not shown, and by this means the jet can be orientated in any desired direction.

When a slow burning gas is supplied to the supply pipe, it passes up the gasway 10 in the socket 9 and into the cavity 4 of the jet body 1, where it divides into two flow paths. Some of the gas flows through the two radial slots 7 into the channel 6 and out of the auxiliary orifices 5 where it is ignited to provide small anchor flames. The dimensions of the slots 7 and the channel 6 are such that there is some restriction to the flow of gas and hence some loss in pressure which ensures stability of the anchor flames. The remainder of the gas flows up the cavity 4 and out of the main orifice 3 where it is ignited to provide a laminar or fan shaped flame. This main flame is constrained from lifting by the presence of the anchor flames. Referring now to FIGURES 4, 5 and 6, a second jet is shown which is substantially the same asthe jet just described except that the body 1 is of greater diameter and semi-circular grooves 11 are formed in the external surface of the body above each of the auxiliary orifices 5. The socket 9 which receives the jet has a windshield 12 so that the anchor flames are partially shielded from the stream of combustion air which diffuses into the main flame. In this construction, the body 1 is strengthened by virtue of the increased diameter of the body and the anchor flames, which have a greater degree of stability than those produced by the construction of jet shown in FIGURES 1 and 2, are guided upwards through the respective grooves 11 before merging with the main flame. The jet can be used to burn certain gases in certain combustion chambers when it is necessary to have an increased distance between the auxiliary orifices 5 and the main orifice 3. To enable the jet shown in FIGURE 1 to be used in similar circumstances, would involve lengthening the body 1 to achieve the said increased distance and this gives rise to manufacturing difficulties due to the relatively thin'wall of the body 1.

Either of the jets described may be composed of a ceramic material or of a heat and corrosion resistant metal. Also, the passages 7 and channels 6 may be varied in dimension and shape according to the supply gas pressure, the nature of the gas and of the application and the desired heat output of the jet. Again, in order to simplify manufacture of the jet the annular channel .6 need not be formed therein and its functions may be served by a similar channel formed in the mating face of the metal socket 9.

The jet shown in FIGURES 1 to 3 may have a windshield 12 and in either case the shield may be separate from or integral with the socket 9.

When using certain gases a higher degree of flame aerati-on is desirable for stability in operation and optimum achievement of heat output. The form of jet shown in FIGURES 1, 2 and 3 provides a relatively stable flame for a given degree of aeration and that shown in FIGURES 4, 5 and 6 provides, relatively speaking, a more stable flame with a lower degree of aeration but reference will now be made to further forms of jet embodying the invention but which provide for a higher degree of aeration than those already described. 7

Referring now to FIGURES 7, 8 and 9 of the drawings, it will be seen that the vertical distance between the exits from the auxiliary orifices 5 and the main orifice 3 is considerably less than in the forms of jet shown in FIGURES 1 to 6. FIGURES 10, 11 and 12 the auxiliary orifices 5 are actually coplanar with the exit from the main orifice 3, the orifices 5 being situated at the top of frusto conical projections 13. This construction encourages a-ir flow under and between the auxiliary flames and into the base of the main flame from the orifice 3. Such inducement of air flow is necessary with those slow burning gases which contain a high proportion of the higher hydrocarbon gases such as propane and butane but is not so necessary in the case of gases such as methane, the chief constituent of natural gas. While, therefore, the form of jet shown in FIGURES 10, 11 and 12 may be used with natural gas and also with a mixture of propane and air, the jet shown in FIGURES 7, 8 and 9 is only suitable for use with natural gas.

Each of the forms of jet described with reference to FIGURES 7, 8 and 9 and FIGURES 10, 11 'and 12 are intended for mounting in a mating socket similar to the socket 9 in FIGURES 3 and 6, but which is formed with a circular groove or channel fulfilling the function of the channel 6 shown in FIGURES 1 and 2 and in FIGURES 4 and 5. No such channel is formed in the jets shown in FIGURES 7, 8 and 9 or in FIGURES 10, 11 and 12. The holes 14 in FIGURES 7 and are countersinkings and are made only to facilitate the formation of the orifices 5 in these figures. A diametral groove 15 of inverted V form is however provided on the underside of each form of jet shown in FIGURES 7, 8 and 9 and 4 i FIGURES 10, 11 and 12, the groove providing com munication between the channel in the mating face of the mounting socket and the auxiliary orifices.

We claim:

1. A non-aerated gas burning jet having a cylindrical body portion provided with a main orifice means which is rectangular in plan and is disposed at the upper end of the body portion at the apex of a substantially wedge shaped cavity formed within the body portion, said cavity being adapted and arranged to produce a fan shaped flame at the main orifice means, and in which the body portion is formed with an annular shoulder in which are formed a plurality of auxiliary orifice means providing, in operation of the jet, flames which serve to maintain ignition of the gas issuing from the main orifice means.

2. A non-aerated gas burning jet as claimed in claim 1 in which the auxiliary orifice means are supplied with gas from an annular groove formed on the underside of the shoulder and which communicateswith radial slots in the body portion.

3. A non-aerated gas burner jet as claimed in claim 1 fitted into a socket having a gas way and in which the auxiliary orifice means are supplied with gas from a diametrally disposed groove formed on the underside of the shoulder and body portion of the jet, the groove being in communication with an annular groove formed in the upper surface of the socket.

4. A non-aerated gas burning jet as claimed in claim 2 in which the exits from the auxiliary orifice means are disposed below the level of the exit from the main orifice means.

5. A non-aerated gas burning jet as claimed in claim 3 in which the exits from the auxiliary orifice means are disposed below the level of the exit from the main orifice means.

6. A non-aerated gas burning jet as claimed in claim 3 in which the exits from the auxiliary orifice means are coplanar with the exit from the main orifice mean-s.

7. A non-aerated gas burning jet as claimed in claim 6 in which the auxiliary orifice means are formed in frustoconical projections from the upper face of the shoulder.

References Cited by the Examiner UNITED STATES PATENTS 790,714 5/1905 Bray 239-558 1,231,726 7/1917 Gault. 1,498,644 6/1924 Clark 239-558 2,103,365 12/1937 Hess 239S48 2,757,963 8/1956 Drell 239601 2,858,729 11/ 1958 Keyes.

FOREIGN PATENTS 1,045,596 7/1953 France. 869,331 8/ 1963 Germany.

EVERETT W. KIRBY, Primary Examiner. 

1. A NON-AERATED GAS BURNING JET HAVING A CYLINDRICAL BODY PORTION PROVIDED WITH A MAIN ORIFICE MEANS WHICH IS RECTANGULAR IN PLAN AND IS DISPOSED AT THE UPPER END OF THE BODY PORTION AT THE APEX OF A SUBSTANTIALLY WEDGE SHAPED CAVITY FORMED WITHIN THE BODY PORTION, SAID CAVITY BEING ADAPTED AND ARRANGED TO PRODUCE A FAN SHAPED FLAME AT THE MAIN ORIFICE MEANS, AND IN WHICH THE BODY PORTION IS FORMED WITH AN ANNULAR SHOULDER IN WHICH ARE FORMED A PLURALITY OF AUXILIARY ORIFICE MEANS PROVIDING, IN OPERATION OF THE JET, FLAMES WHICH SERVE TO MAINTAIN IGNITION OF THE GAS ISSUING FROM THE MAIN ORIFICE MEANS. 